In order to determine material characteristics which represent the behavior of materials under the influence of external forces, it is well known to subject material test samples prepared from the corresponding material to standardized material tests. One example of such a material test is what is known as the tensile test, by way of which the tensile strength and further material characteristics of a material can be determined. In such material tests, a flat material test sample comprising a rectangular test cutting and a flat sample head is clamped on both sides into a material testing machine using a clamping device, whereupon a load is exerted on the material test sample via the clamping devices. Currently known clamping devices normally operate on the pincer principle, in which the end of the material test sample is gripped or clamped in a pincer-like manner by the clamping device. Such clamping devices have proven successful in particular in the modeling of unidirectional tensile deformations, as occur in particular during the tensile test. However, they reach physical limits when symmetrical alternating tensile and compressive loading is intended to take place, i.e. R=−1, in which case:R=Fmin/Fmax=σmin/σmax 
where Fmin is the compressive force with a negative sign and Fmax is the tensile force with a positive sign. In such alternating tensile and compressive loading, a jump function frequently occurs at the transition from the tensile loading to the compressive loading, because the material test sample begins to slip since the clamping action of the clamping devices that operate according to the pincer principle is insufficient.
Currently, this problem is solved in that symmetrical loading is dispensed with. The material test is thus run in what is known as the range of pulsating tensile stresses where R=0. This means that the tensile force fluctuates, with the minimum stress being 0. Accordingly, the material test sample is not exposed to any compressive force, and so slipping of the material test sample is prevented.